DTC P084C (6-Speed A/T)

DTC P084C  : Line Pressure Switch Stuck ON

NOTE: 

• Before you troubleshoot, review the General Troubleshooting Information - Refer to: How to Troubleshoot the A/T System .
• If DTC P084C is stored in the PCM, engine torque is limited because of the fail-safe function.

DTC (A/T)

1. Problem verification

   - 1. Turn the vehicle to the ON mode.

   - 2. Clear the DTC with the HDS.

   - 3. Check the parameter (s) below with the HDS.

   Signal	Threshold		Current conditions
   	Values	Unit	Values	Unit
   Line Pressure Switch	ON

   Do the current condition (s) match the threshold?

   YES 

   The failure is duplicated. Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Check for poor connections and loose terminals between the line pressure switch and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.

2. Determine possible failure area (line pressure switch, others)

   - 1. Turn the vehicle to the OFF (LOCK) mode.

   - 2. Disconnect the following connector.

   Line pressure switch 1P connector

   - 3. Turn the vehicle to the ON mode.

   - 4. Check the parameter (s) below with the HDS.

   Signal	Threshold		Current conditions
   	Values	Unit	Values	Unit
   Line Pressure Switch	OFF

   Do the current condition (s) match the threshold?

   YES 

   Replace the line pressure switch .

   NO 

   Go to step 3.

3. Shorted wire check (OPPLSW line)

   - 1. Turn the vehicle to the OFF (LOCK) mode.

   - 2. Jump the SCS line with the HDS, and wait more than 1 minute.

   - 3. Disconnect the following connector.

   PCM connector B (51P)

   - 4. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Line pressure switch 1P connector: disconnected
   	PCM connector B (51P): disconnected
   Test point 1	PCM connector B (51P) No. 37 - Refer to: PCM Connector for Inputs and Outputs (16-20 6-Speed A/T) .
   Test point 2	Body ground

   Is there continuity?

   YES 

   Repair a short to ground in the OPPLSW wire between the line pressure switch and the PCM.

   NO 

   The OPPLSW wire is OK. Replace the PCM - Refer to: PCM Removal and Installation (6-Speed A/T, 16-18 9-Speed A/T) .